Hot press machine

Abstract

A lower mold includes: refrigerant ejection ports in its press-molding surface; refrigerant guide grooves in the press-molding surface to guide a refrigerant ejected from the refrigerant ejection ports to an outer portion of the press-molding surface with the refrigerant being in contact with a workpiece; a single connecting groove connected to the refrigerant guide grooves and formed at the outer portion of the press-molding surface into which the refrigerant flows through the refrigerant guide grooves; and discharge ports in the connecting groove. Each of the refrigerant discharge ports is formed at a part of the connecting groove apart from the connecting points between the connecting groove and the refrigerant guide grooves.

What is claimed is: 
     
       1. A hot press machine for press-molding a heated metal workpiece and cooling the pressed workpiece using a refrigerant, the machine comprising:
 an upper mold and a lower mold, each having a press-molding surface for press-molding the workpiece into a predetermined shape, the press-molding surfaces corresponding to each other, wherein 
 at least one of the upper mold or the lower mold includes:
 a refrigerant ejection port in the press-molding surface to eject the refrigerant; 
 a plurality of refrigerant guide grooves in the press-molding surface to guide the refrigerant ejected from the refrigerant ejection port to an outer portion of the press-molding surface with the refrigerant being in contact with the workpiece; 
 a single connecting groove connected to the refrigerant guide grooves and formed at the outer portion of the press-molding surface into which the refrigerant flows from the refrigerant guide grooves; and 
 a refrigerant discharge port in the connecting groove, 
 
 the refrigerant discharge port is formed at a part of the connecting groove apart from connecting points between the connecting groove and the refrigerant guide grooves, 
 the refrigerant ejection port includes a plurality of refrigerant ejection ports arranged at an interval in the press-molding surface, 
 the press-molding surface extends in a longitudinal direction corresponding to a length direction of the workpiece, 
 at least a part of the press-molding surface has the refrigerant ejection ports arranged alternately on one side and the other side of the press-molding surface, when the press-molding surface is viewed in the longitudinal direction, 
 some of the refrigerant guide grooves extend from each of the refrigerant ejection ports formed on the one side of the press-molding surface toward the other side of the press-molding surface, 
 the others of the refrigerant guide grooves extend from each of the refrigerant ejection ports formed on the other side of the press-molding surface toward the one side of the press-molding surface, 
 each of the upper and the lower molds includes: the refrigerant ejection ports arranged alternately; and the refrigerant guide grooves extending from the refrigerant ejection ports, and 
 each of the refrigerant ejection ports on the one side of one of the upper and the lower molds is located in an intermediate position between adjacent ones of the refrigerant ejection ports on the one side of the other of the molds, and each of the refrigerant ejection ports on the other side of one of the upper and the lower molds is located in an intermediate position between adjacent ones of the refrigerant ejection ports on the other side of the other of the molds. 
 
     
     
       2. The machine of  claim 1 , wherein
 the refrigerant guide grooves extend from the refrigerant ejection port not in the longitudinal direction but in a transverse direction of the press-molding surface. 
 
     
     
       3. The machine of  claim 1 , wherein
 in order to provide a press-molded product with a substantially concave cross section from the workpiece, the press molding surface of each of the upper and the lower molds includes: 
 a top wall molding part configured to mold a top wall of the concave press-molded product; 
 side wall molding parts continuous with the top wall molding part and configured to mold side walls of the press-molded product, the side wall molding parts corresponding to each other; and 
 flange molding parts continuous with the respective side wall molding parts and configured to mold flanges of the press-molded product, 
 the refrigerant ejection port is formed in the top wall molding part of the press-molding surface, 
 the refrigerant guide grooves extend from the refrigerant ejection ports in the top wall molding part through the side wall molding parts to the flange molding parts that form the outer portion of the press-molding surface, and 
 the refrigerant discharge port is formed in the flange molding part. 
 
     
     
       4. The machine of  claim 1 , wherein
 the refrigerant is a liquid. 
 
     
     
       5. A hot press machine for press-molding a heated metal workpiece and cooling the pressed workpiece using a refrigerant, the machine comprising:
 an upper mold and a lower mold, each having a press-molding surface for press-molding the workpiece into a predetermined shape, the press-molding surfaces corresponding to each other, wherein 
 at least one of the upper mold or the lower mold includes:
 a refrigerant ejection port in the press-molding surface to eject the refrigerant; 
 a plurality of refrigerant guide grooves in the press-molding surface to guide the refrigerant ejected from the refrigerant ejection port to an outer portion of the press-molding surface with the refrigerant being in contact with the workpiece; 
 a single connecting groove connected to the refrigerant guide grooves and formed at the outer portion of the press-molding surface into which the refrigerant flows from the refrigerant guide grooves; and 
 a refrigerant discharge port in the connecting groove, 
 
 the refrigerant discharge port is formed at a part of the connecting groove apart from connecting points between the connecting groove and the refrigerant guide grooves, 
 the refrigerant ejection port includes a plurality of refrigerant ejection ports arranged at an interval in the press-molding surface, 
 the press-molding surface extends in a longitudinal direction corresponding to a length direction of the workpiece, 
 at least a part of the press-molding surface has the refrigerant ejection ports arranged alternately on one side and the other side of the press-molding surface, when the press-molding surface is viewed in the longitudinal direction, 
 some of the refrigerant guide grooves extend from each of the refrigerant ejection ports formed on the one side of the press-molding surface toward the other side of the press-molding surface, 
 the others of the refrigerant guide grooves extend from each of the refrigerant ejection ports formed on the other side of the press-molding surface toward the one side of the press-molding surface, 
 in order to provide a press-molded product with a substantially concave cross section from the workpiece, the press molding surface of each of the upper and the lower molds includes:
 a top wall molding part configured to mold a top wall of the concave press-molded product; 
 side wall molding parts continuous with the top wall molding part and configured to mold side walls of the press-molded product, the side wall molding parts corresponding to each other; and 
 flange molding parts continuous with the respective side wall molding parts and configured to mold flanges of the press-molded product, 
 the refrigerant ejection port is formed in the top wall molding part of the press-molding surface, 
 the refrigerant guide grooves extend from the refrigerant ejection ports in the top wall molding part through the side wall molding parts to the flange molding parts that form the outer portion of the press-molding surface, and 
 the refrigerant discharge port is formed in the flange molding part, and 
 
 the press molding surface of each of the upper and the lower molds is configured to provide a press-molded product in which:
 each of the flanges of the press-molded product includes a first part and a second part, the first part requiring a higher surface accuracy than the second part, and 
 each of the refrigerant guide grooves extends not toward the first part of an associated one of the flange molding parts but toward the second part. 
 
 
     
     
       6. The machine of  claim 5 , wherein
 the refrigerant guide grooves extend from the refrigerant ejection port not in the longitudinal direction but in a transverse direction of the press-molding surface. 
 
     
     
       7. The machine of  claim 5 , wherein
 the refrigerant is a liquid.